The subject matter discussed in the background section should not be assumed to be prior art merely as a result of its mention in the background section. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subject matter in the background section merely represents different approaches, which in and of themselves may also be inventions.
Touch sensitive devices such as touch screen displays, track pads and graphic tablets have a touch sensitive surface that can sense when a user of the touch screen device brings an object such as a fingertip into contact with a portion of the touch sensitive surface and that sends signals to a processor from which the processor can determine which portion of the touch sensitive surface sensing surface has been contacted. By monitoring the signals from the touch sensitive surface over time, it is possible to assemble tracking data characteristic of a path of movement of the object from a moment of that the object contacts with the touch sensitive surface until the object separates from touch sensitive surface.
Conventionally, such a movement is referred to as a stroke. It will be appreciated that processing user input on a stroke by stroke basis offers many advantages. One advantage is that stroke type movements such as finger pointing, gesticulation and handwriting are used to convey information in a whole host of human interactions. By sensing gestures of this type, touch sensitive surfaces allow more natural interactions between users and touch sensitive devices thereby increasing the usability and adoption rate of such devices while lowering training costs.